In recent years, various types of information services such as retrieval service, electronic commerce service, and music delivery service have been actively offered using a personal computer in which a browser is installed.
For example, electronic commerce service is achieved in a form that installs a browser and an electronic wallet application in a personal computer, and activates the electronic wallet application from the browser to use the facilities of the electronic wallet application. FIG. 1(a) is a schematic block diagram of an EC system of the prior art.
The EC system, as shown in FIG. 1(a), comprises a personal computer in which a browser 1406 and an electronic wallet application 1407 are installed, an electronic value server 1403 that creates and issues electronic value such as electronic tickets and prepaid electronic money, a service server 1405 that provides service corresponding to paid costs, a settlement server 1404 that performs account settlement processing in banks, credit service companies, or settlement institutions, and an information server 1402 that provides online information concerning electronic value and vends electronic value, wherein these components are linked by the Internet 1400.
For example, assuming that information service provided by the service server 1405 is paid by prepaid type electronic money managed by the electronic wallet application 1407, the personal computer 1401 receives HTML page data including a link for activating the electronic wallet application 1407 from the service server 1405 and displays its contents on a browser window 1412 of a display screen 1411 (see FIG. 1(b)). When a user selects the link for activating the electronic wallet application 1407, the browser 1406 activates the electronic wallet application 1407 and an electronic wallet window 1413 is displayed on the display screen 1411. The user manipulates the activated electronic wallet application 1407 and pays a required cost to the service server 1405 by the prepaid type electronic money managed by the electronic wallet application 1407. If the prepaid type electronic money is lacking, the user manipulates the electronic wallet application 1407 to purchase prepaid type electronic money via the information server 1402 and downloads new prepaid type electronic money from the electronic value server 1403. When the required cost is paid, and to ensure security for the downloading of prepaid type electronic money, between the electronic wallet application 1407 and the service server 1406, and between the electronic wallet application 1407 and the electronic value server 1403, communications are performed using an electronic wallet protocol 1409, instead of the HTTP protocol 1408.
However, in an attempt to provide the same services for mobile terminals which have smaller display screens and are poorer in resources such as memory than personal computers, conventional mechanisms have been lacking in the capability to display the browser window and the electronic wallet window on one screen at a time because of the small display screen of the mobile terminals, requiring the mobile terminals to allocate a display memory for each application and providing users with the inconvenience of switching and using screens for each application.
Also, since mobile terminals such as portable telephones, in most cases, have communication parts optimized depending on manufacturers and models, and there is no standard API for the communication parts, it has been necessary to develop an electronic wallet protocol for each model.
Also, in mobile terminals such as portable telephones, since the size of data that can be transferred at a time is smaller, compared with personal computers, large-capacity electronic value containing image data cannot be downloaded and, in some cases, have been unusable in mobile terminals.